To replace the classic Teams app, you should install the new Teams client. Microsoft has rolled out the new Teams client, which replaces the classic version. If your classic Teams app is no longer working, you can download the new Teams client from the official Microsoft website or use the new Teams web app on supported browsers if you cannot upgrade your device.
Keep in mind that the classic Teams client reached the end of support on July 1, 2025, and is no longer available for use after that date. If you need assistance with the installation or encounter any issues, you may want to contact your IT department for help.
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